package com.nuan.shiro.config;

import com.nuan.shiro.constants.CodeEnum;
import com.nuan.shiro.constants.JWTToken;
import com.nuan.shiro.constants.ResultUtil;
import com.nuan.shiro.utils.WebUtilsPro;
import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.authc.AuthenticationToken;
import org.apache.shiro.subject.Subject;
import org.apache.shiro.web.filter.authc.BasicHttpAuthenticationFilter;
import org.apache.shiro.web.filter.authz.AuthorizationFilter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.HttpStatus;
import org.springframework.web.bind.annotation.RequestMethod;

import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.net.URLEncoder;

/**
 * 直接配置路径权限
 */
public class JwtOAuthorizationFilter extends BasicHttpAuthenticationFilter
{

    private Logger logger= LoggerFactory.getLogger(this.getClass());
    public JwtOAuthorizationFilter() {
    }
    public boolean isAccessAllowed(ServletRequest request, ServletResponse response, Object mappedValue)
    {

        return false;

    }

    /**
     * 拦截拒绝后使用
     * @param request
     * @param response
     * @return
     */
    @Override
    protected boolean onAccessDenied(ServletRequest request, ServletResponse response) {
        //获取请求token，如果token不存在，直接返回401
        if (!isLoginAttempt(request, response)) {
            WebUtilsPro.writer(ResultUtil.error(CodeEnum.AUTH_LOGIN),request,response);
        }
        //如果存在，则进入 executeLogin 方法执行登入，检查 token 是否正确
        try {
            executeLogin(request, response);
            return true;
        } catch (Exception e)
        {
            //token 错误
            e.printStackTrace();
            responseError(request, response, e.getMessage());
           // WebUtilsPro.writer(ResultUtil.error(CodeEnum.AUTH_LOGIN),request,response);
            //如果请求头不存在 token，则可能是执行登陆操作或者是游客状态访问，无需检查 token，直接返回 true
            return false;
        }
    }

    @Override
    protected boolean isLoginAttempt(ServletRequest request, ServletResponse response) {
        HttpServletRequest req = (HttpServletRequest) request;
        String token = req.getHeader("token");
        return token != null;
    }

    /**
     * 执行登陆操作
     */
    @Override
    protected boolean executeLogin(ServletRequest request, ServletResponse response) throws Exception {
        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
        String token = httpServletRequest.getHeader("token");
        JWTToken jwtToken = new JWTToken(token);
        // 提交给realm进行登入，如果错误它会抛出异常并被捕获
        getSubject(request, response).login(jwtToken);
        // 如果没有抛出异常则代表登入成功，返回true
        return true;
    }

//    /**
//     * 对跨域提供支持
//     */
//    @Override
//    protected boolean preHandle(ServletRequest request, ServletResponse response) throws Exception {
//        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
//        HttpServletResponse httpServletResponse = (HttpServletResponse) response;
//        httpServletResponse.setHeader("Access-control-Allow-Origin", httpServletRequest.getHeader("Origin"));
//        httpServletResponse.setHeader("Access-Control-Allow-Methods", "GET,POST,OPTIONS,PUT,DELETE");
//        httpServletResponse.setHeader("Access-Control-Allow-Headers", httpServletRequest.getHeader("Access-Control-Request-Headers"));
//        // 跨域时会首先发送一个option请求，这里我们给option请求直接返回正常状态
//        if (httpServletRequest.getMethod().equals(RequestMethod.OPTIONS.name())) {
//            httpServletResponse.setStatus(HttpStatus.OK.value());
//            return false;
//        }
//        return super.preHandle(request, response);
//    }

    /**
     * 将非法请求跳转到 /unauthorized/**
     */
    private void responseError(ServletRequest request,ServletResponse response, String message) {
//        try {
//            HttpServletResponse httpServletResponse = (HttpServletResponse) response;
//            //设置编码，否则中文字符在重定向时会变为空字符串
//            message = URLEncoder.encode(message, "UTF-8");
//            httpServletResponse.sendRedirect("/unauthorized/" + message);
            WebUtilsPro.writer(ResultUtil.error(CodeEnum.AUTH_ERROR),request,response);
//        } catch (IOException e) {
//            logger.error(e.getMessage());
//        }
    }

}